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Primes of the form 6x^2 + 17y^2.
3

%I #19 Sep 08 2022 08:45:33

%S 17,23,41,71,113,167,233,311,401,431,449,479,503,521,617,641,719,743,

%T 809,839,857,881,887,911,929,983,1031,1049,1151,1193,1217,1289,1319,

%U 1367,1433,1439,1553,1559,1601,1697,1847,2063,2081,2111,2153,2207

%N Primes of the form 6x^2 + 17y^2.

%C Discriminant = -408. See A139827 for more information.

%H Vincenzo Librandi and Ray Chandler, <a href="/A139843/b139843.txt">Table of n, a(n) for n = 1..10000</a> [First 1000 terms from Vincenzo Librandi]

%H N. J. A. Sloane et al., <a href="https://oeis.org/wiki/Binary_Quadratic_Forms_and_OEIS">Binary Quadratic Forms and OEIS</a> (Index to related sequences, programs, references)

%F The primes are congruent to {17, 23, 41, 65, 71, 95, 113, 143, 167, 209, 215, 233, 311, 329, 335, 377, 401} (mod 408).

%t QuadPrimes2[6, 0, 17, 10000] (* see A106856 *)

%o (Magma) [ p: p in PrimesUpTo(3000) | p mod 408 in {17, 23, 41, 65, 71, 95, 113, 143, 167, 209, 215, 233, 311, 329, 335, 377, 401}]; // _Vincenzo Librandi_, Jul 29 2012

%o (PARI) list(lim)=my(v=List([17]), s=[23, 41, 65, 71, 95, 113, 143, 167, 209, 215, 233, 311, 329, 335, 377, 401]); forprime(p=23, lim, if(setsearch(s, p%408), listput(v, p))); Vec(v) \\ _Charles R Greathouse IV_, Feb 10 2017

%K nonn,easy

%O 1,1

%A _T. D. Noe_, May 02 2008